"Law enforcement officials told NBC News that the explosives were classified as low — meaning that they traveled at under 3,300 feet per second. That is not enough to create a blast wave, which can kill people from air compression and blow out faraway windows, but it is enough to propel shrapnel a great distance.

A pressure cooker, in its everyday use, speeds cooking by creating a tight seal and building pressure inside the pot. Converting it to a bomb sheaths the explosives in a metal casing, which blows apart when the bomb is detonated and adds to the shrapnel already packed inside.

Rep. Michael McCaul, R-Texas, chair of the House Homeland Security Committee, said that he knew of two ways to detonate a pressure cooker bomb — with a device placed on the cooker or by remote, such as by cellphone. Law enforcement could use records to track a cellphone detonation, he said.

One of the three devices that was to be used in an attempted bomb attack in Times Square in 2010 was a pressure cooker. Earlier that year, terrorists used a pressure cooker bomb in an attack in Pakistan. And in 2006, more than 130 people were killed on the transit system of Mumbai, India, when pressure cookers loaded with explosives were placed on trains.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

I'm not sure the public realizes that jihadist terrrorist acts, though ideologically-aligned with Al Qaeda's mission, are not necessarily carried out under the command of a hierarchal unit of Al Qaeda or any formal entity. The enemy includes a diffuse network of possibly leaderlesscells and self-assigned individuals not formally tied to any entity.

They share the central idea to "kill the Satan."

Of course, there are sponsoring nations that support attacks such as these in both concrete and ideological terms.

To add to the challenge...Just because we see the actor(s) here employing inexpensive means we can't assume they were not deployed by an enemy state as part of a program.

Always the question...how to prosecute?!!

One thing we do know. Acts such as these are DESIGNED to enrage, confuse, intimidate, depress and demoralize the United States. The CHIEF AIM of militant jihad is to spotlight the USA in a state of AGONY in order to embolden militant jihad AND recruit.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

"The explosives used in the Boston Marathon bombing were crude devices often called pressure cooker bombs, according to a person briefed on the investigation.

The person spoke on condition of anonymity because the investigation in Boston was still ongoing.

While the devices have been frequently used in Afghanistan, India and Pakistan, in recent years they have also shown up in plots in the U.S. and France.

Explosives typically are placed inside a pressure cooker _ a commonplace cooking utensil in many countries _ and the device is then detonated using everyday electronic equipment such as digital watches, garage door openers, cellphones or pagers. Pressure builds inside the container and shrapnel is expelled. Al-Qaida affiliates have provided training and manuals on how to build such devices.

Here's a look at some of the most recent container bombs:

___

February 2013: A bomb hidden in a pressure cooker explodes inside a restaurant in northern Afghanistan, killing five people.

October 2012: French police find bomb-making materials in an underground parking lot near Paris as part of a probe into an attack on a kosher grocery. The discovery includes bags of potassium nitrate, sulfur, headlight bulbs and a container used as a make-shift pressure cooker.

May 2012: U.S. jurors hear that explosives experts had found a pressure cooker containing smokeless gunpowder and other material in the Texas motel room of a soldier accused of planning to blow up Fort Hood military troops and other personnel.

May 2010: One of the three devices used in the May 2010 Times Square attempted bombing was a pressure cooker, according to a joint FBI and Homeland Security intelligence report issued in July 2010.

March 2006: A series of bombings kill 20 people in India. One bomb _ at a temple in the northern city of Varanasi where five people died _ was placed in a pressure cooker and detonated by a timing device.

December 2004: Ten accused Islamic militants are convicted for their roles in a plot to blow up a Christmas market in the eastern French city of Strasbourg on New Year's Eve 2000. Authorities say the group had planned to blow up containers packed with explosives, a technique they allegedly learned in Afghan camps.

August 2002: Explosives packed in a pressure cooker shake a shopping mall in Katmandu, the capital of Nepal. Shops are damaged but there are no casualties."

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

my bet would be, lets see if i am right, a male, not african american nor arab, below age 32, loner (meaning worked alone), lives in new england (rhode island, vt (doubful), new hampshire (maybe) maine (maybier), Massachusetts? (I'd guess). forensics like bought pressure cookers on criagslist or black powder and looked sketchy will be his demise. He thinks he thought of everything but he has made a mistake somewhere. Photos could also aide in his capture as has done soo often in the past.

Mikiesplace, good to see you! I won't ask what leads you to all that. For obvious reasons.

I thought of a copycat too. Someone who wanted it to look like a jihadist attack. In any case, I would like to personally string him up by his you -know-whats.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

A thought that crossed my mind was this was racially motivated. It was Jackie Robinson Day in Major League Baseball, and all of the players, coaches and managers were wearing # 42 in his honor ( 42 was Robinson's number ). The locations of the bombs were only 1 1/2 miles from Fenway Park, and a game ended only an hour before detonation. International or home-grown, these terrorists need to be caught and punished. MarlyB, I volunteer my services as Dave's assistant, free of charge ......

The NYTimes has published some Joint Terrorism Task Force of Boston via Reuters forensic photographs of the explosive device. The slide show can be viewed here:

http://www.nytimes.com/slideshow/2013/04/17/us/20130417_DEVICE.html

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

my bet would be, lets see if i am right, a male, not african american nor arab, below age 32, loner (meaning worked alone), lives in new england (rhode island, vt (doubful), new hampshire (maybe) maine (maybier), Massachusetts? (I'd guess). forensics like bought pressure cookers on criagslist or black powder and looked sketchy will be his demise. He thinks he thought of everything but he has made a mistake somewhere. Photos could also aide in his capture as has done soo often in the past.

Mikisplace, I'm in awe over your profiling, especially after the news broke that (allegedly) it is a young male and is probably a lone wolf. That's skills, Bruh and I'm remembering when members suggested you write a book.

Well, I was not far off and thinking somewhere along those lines, but I'm compelled (not brainwashed) to think--Fairly Religious, but not extreme, educated foreign student slightly into the Libertarian movement, highly adamant about foreign policy (Isreal + drones).

I trust that the FBI and the ATF are crossing all their T's and dotting all their I's given this nations history of bombings here on our own soil. We've had KKK Church bombings, Federal Buildings, olympic venues and of course 9/11 where the TT's where bombed twice.

I think we'll know soon, I would hope media does a double check on what they report and how they report it. Does anyone remeber what happened at the olympics in '96? I was kind of young then, but I recall a jury of public opinion practically ruined an officers life by casting suspicion on him due to reporting, when in fact the officer was a hero.

Yes, of course, we haven't forgotten we are a country under the rule of law.

And yeah, It's a waiting game at this point. Of course.

As for the wrongly accused LonnaNJ mentions - a quick google using search keywords "wrongly accused" "officer" "Olympics" "1996" reveals his forgotten name. Richard Jewell died August 29, 2007, ten years after his ordeal. Jewell was collateral damage in the aftermath, soon to fade. Thanks, LonnaNJ.

Richard Jewell, the former security guard who was erroneously linked to the 1996 Olympic bombing, died Wednesday, the Georgia Bureau of Investigation said.

Jewell, 44, was found dead in his west Georgia home, GBI spokesman John Bankhead said.

"There's no suspicion whatsoever of any type of foul play. He had been at home sick since the end of February with kidney problems," said Meriwether County Coroner Johnny Worley.

The GBI planned to do an autopsy Thursday, Bankhead said.

Lin Wood, Jewell's longtime attorney, said in an e-mail to The Associated Press that he was "devastated" by the news. He declined to comment further, saying he was in New York trying to get back to Atlanta.

Jewell was initially hailed as a hero for spotting a suspicious backpack in a park and moving people out of harm's way just before a bomb exploded during a concert at the Atlanta Summer Olympics.

The blast killed one and injured 111 others. Three days after the bombing, an unattributed report in The Atlanta Journal-Constitution described him as "the focus" of the investigation.

Other media, to varying degrees, also linked Jewell to the investigation. He was never arrested or charged, although he was questioned and was a subject of search warrants. The media circus that followed the FBI investigation obscured the fact that Jewell saved the lives of many members of the technical staff working on live TV coverage of the Olympics.

“Richard ran all the way up and down the four stories of the tower and evacuated everybody, it must have been between 40 and 50 people. Seconds later the thing exploded,” said Bruce Rodgers, president of Tribe Inc and designer of the AT&T Global Village, where the explosion happened.

The next day, when Rodgers went back up the tower, “My whole corner was completely obliterated," he said. "steel shrapnel, pipe material lodged into the decking of the structure and embedded inches into the ceiling. The chairs that we usually sat in were completely sheared and ripped apart.

"Had he not gotten those people out, I know that at least 20 people on the first two floors of the tower would be dead.”

As recently as last year, Jewell was working as a sheriff's deputy.

Eighty-eight days after the initial news report, U.S. Attorney Kent Alexander issued a statement saying Jewell "is not a target" of the bombing investigation and that the "unusual and intense publicity" surrounding him was "neither designed nor desired by the FBI, and in fact interfered with the investigation."

In 1997, U.S. Attorney General Janet Reno expressed regret over the leak regarding Jewell. "I'm very sorry it happened," she told reporters. "I think we owe him an apology."

The Atlanta newspaper never settled a lawsuit Jewell filed against it. The case was still pending as of last year. A lawyer for the newspaper did not immediately return calls seeking comment. Eventually, the bomber turned out to be anti-government extremist Eric Rudolph, who also planted three other bombs in the Atlanta area and in Birmingham, Ala. Those explosives killed a police officer, maimed a nurse and injured several other people.

Rudolph was captured after spending five years hiding out in the mountains of western North Carolina. He pleaded guilty to all four bombings last year and is serving life in prison. Jewell told the AP last year that Rudolph's conviction helped, but he believed some people still remember him as a suspect rather than for the two days in which he was praised as a hero.

"For that two days, my mother had a great deal of pride in me -- that I had done something good and that she was my mother, and that was taken away from her," Jewell said around the time of the 10th anniversary of the bombing. "She'll never get that back, and there's no way I can give that back to her."

A year ago, Gov. Sonny Perdue commended Jewell at a bombing anniversary event. "This is what I think is the right thing to do," Perdue declared as he handed a certificate to Jewell.

Jewell said: "I never expected this day to ever happen. I'm just glad that it did."

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

thanks for the vote of confidence lonnaNJ but the fat lady has not officially sung yet. (sung? is that right?) marlyb please help? lol. if i am correct on 99 percent and am asked, i shall reveal my reasoning, if i am wrong, i owe the crew a round at the next gathering.

MIKIESPLACE you are 100%right on. The song has yet to be sung, And, since we are a country ruled by law I can only assure everyone my heartfelt desire to snip the culprit's nipples off with a pair of nail clippers as the opening salvo to death by 1000 cuts should be translated as "The sooner the snare, the better. May justice prevail."

Annnd...I have my own hunchettes why you listed those characteristics, Mikie. But I ain't sayin' cuz if you are wrong I will be glad for a free drap o' th' dew.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

NPR’s Dan Bobkopf (sp?) in Boston- FBI prepared to release photos – screengrab of man looking for - and ask for the public’s help to locate that individual. After considering the pros and cons of releasing the photos the FBI…Re: Napolitano – Not suspects.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

NOTE: These are my raw notes taken simultaneous during the interview. NOT VERBATIM! Please refer to NPR interview with Dartmouth Computer Science Professor Fehreid.

NPR: re: Reddit Find Boston Bombers 'circle the black backpack'...

PROF FEHREID: ...massive amount of data…more eyes usually means better analysis…many things being said that are wrong…conclusions…vigilante mentality…provides law enforcement a large amount of data…but doesn’t belong in the hands of the crowd.

NPR: Sped up technology -- Reputable media, good reporters reported an arrest…how many can LE show the public without jeopardizing the investigation?

PROF FEHREID - Double-edged sword…need access..price to be paid in the distraction – takes away from efforts focused on the investigation – false reports….spread now not just through media but fast and furious through twitter and facebook – bad for investigation because they are a distraction.

NPR: JFK assassination – ordinary citizens provided photographs?

PROF FEHRIED: - but now everybody has a phone… and can disseminate at great speed. Volume and speed is something new.

Pictures of a man wearing a baseball cap backwards…dangerous. Yes…reputations…families at stake.

FOUR TYPES OF SOFTWARE

FACIAL RECOGNITION AND DETECTION SOFTWARE – Face detection – find a face in the image…distinct from the scene. Quick analysis is there a person in here? Recognition – Person of interest – Find all the faces that look like this one. Sophisticated and retail.

TIME / SPACE MAPPING– Smart phones – Geo tagged GPS location triangulation from cell towers and time of day. Photo associated with time stamp and Geo stamp. Can lay images out across space and time over a map – every five seconds – pieced together the event. Seen in advertising – creating video out of still.Can go further – multiple images from diff vantage points to create a 3d view out of 2d which you can spin around and examine.

AUTHENTIFICATION - Photoshop – Intentional or unintentional image – splicing in or removing – technology uses a signature to make and model of camera and can determine if it has been altered. Doctored photographs are a problem cant have in the mix, incorrect leads, time consuming.

Crowd can help supply photos but crowd has a lot of noise and inaccuracies so let’s let the professionals do it.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

FBI Special Agent Richard DeLaurier (sp?) – Pursued thousand of leads and tips…careful process…"single person of interest"…(lists cooperative national and international agencies) indeed through that process …developed a second suspect. These suspects are associated…#2 set down a bag at the Forum (sp) restaurant. #1 = #2 observed walking (together) at Boyleston and Glouster (sp.)

Refers public to FBI website. Asks public to view ONLY THESE PHOTOS in order to not create undue work. Reminded public that public has played a critical role for over 100 years. The nation is counting on those with information to come forward and provide it to us. No information no matter how small…is critical…Armed and extremely dangerous.

Do not approach …Do not take action on own.

No additional imminent danger that we are aware of.

SUSPECT #2 IS THE ONLY ONE SEEN TO HAVE BEEN PLANTING DEVICE.

REFER TO THE FBI WEBSITE FOR PHOTOS AND TO PROVIDE TIPS.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

That's - DON'T REFER TO PHOTOGRAPHS OF SUSPECTS #1 AND #2 APART FROM THOSE POSTED ON THE FBI'S WEBSITE.

Public - Please refer to previous post here which discusses how a glut of reponses to unauthorized photographs hinder investigations.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

Yes, RobertHoven4578. It's a common technique. You see it in 'Battle of Algiers' - a docu-drama that serves as a sort of primer to military strategists. Cafe bombings. A timed sequence. One planted in the cafe, one planted outside to kill those who flee. Another planted further down to get first reponders, and so on.

RobertHoven4578 says ...

They were setting a Series, Making the people run where they wanted them to go. Just 2 more in that series and it would have been a lot worse. This is a "Thinking Person" The WORST kind.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

One suspect (Black Hat) was shot and killed, one with the white hat still at large. One MIT Officer subcumbed to his injuries SAD, the Transit Officer was shot and wounded and his condition is pretty serious.

Slept in this morning, so just got the news. Chechen, huh. Now isn't THAT something. I have my own little theory right now, but I ain't sayin' a mumblin' word til'...as Mikie says, the fat lady sings.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

I expect we have a little while yet in the investigation before the fat lady sings. Stay tuned!

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

IF i were to err astride the law, would that necessarily implicate the Irish Republican Army? Why then make attempts to implicate the homeland where these families fled and sought asylum? patience, wait.

At least we civilians out here have the luxury of waiting. Meanwhile, the professionals toil against the clock...

I am listening to NPR's coverage of the situation in Watertown. Lots of ideas about why flashbang's being used. It seems like a no-brainer to me.

I'm praying they capture the little sob alive. I want him squeezed.

The whole thing, as it develops, is working my nerves.

NPR is interviewing a Mr. Cassal(sp), Private Investigator. These are my raw notes...paraphrase of course.

Cassal points out we don't want to see any other officers injured. Figures he was wounded in the 1st 20 rounds. Figures hes low on ammo from 2 fights. Max will last 49 hr. may have a pipe bomb or the like. May try to rush to get a police-assisted suicide. Offer arrest...come out under police terms. Wounded, come out to get aid. Utter disregard for life - most likely he won't come out.

Wearing an explosive device? Would change equation but won't get to that point. Boat is surrounded by a safe distance. Bunkers and sufficient weapons in place, perimeter maintained until he comes out hands up or...until situation indicates he has passed or until they can go in knowing it's booby trapped.

May not make a rational action? Sure but neither have his other actions been. Police have all the time they need. Officers can be relieved.

If he's wounded, positive for the police, but assume he is not.

Badly wounded? Hasten for that reason as he may expire before they can find anything else out? Police are not going to risk any more lives (in reference to hastening to get him out). This is a limited negotiation. Will try to talk...dunno if he's answering back. Thermal imaging...aggressive K9 to go in and make contact find out what is happening.

Did police help him get away? No. Not at all. Most dangerous job is the police officer in the squad car, not SWAT. Officers will be very judicious about how they fire in.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas

NPR reports that authorities used the negotiative approach to a 'wounded animal.' Reporters are remarking that the older brother, Tamerlan Tsanaev, was more radicalized, more hardened and associated with extremist groups.

According to NPR in 2011 FBI interviewed Tamerlan because of those ties.

Congratulations and my deepest gratitute to the thousands who pursued the suspects, to those who ran Dzhokhar to ground, and to the negotiators who captured him alive.

My deepest condolences to the families and friendsof the murdered.

God heal the wounded.Bless and hold them close.

God comfort the first responders, the medical personnel continuing to provide care. God speed his healing graceto all those touched by this monstrosity.

God heal all our hearts. May Your Justice prevail.

Aim at the high mark and you will hit it. No, not the first time, not the second time and maybe not the third. But keep on aiming and keep on shooting for only practice will make you perfect. Finally you'll hit the bull's-eye of success.

— Annie Oakley , Annie Oakley exhibit at the National Cowgirl Museum and Hall of Fame in Fort Worth, Texas